Acquired aganglionosis following surgery for Hirschsprung's disease: a report of five cases during a 33-year experience with pull-through procedures.

Acquired Hirschsprung's disease is a rare and controversial form of colonic aganglionosis. Little is known about its aetiology and pathogenesis. We report five cases encountered amongst 173 long-term follow-up patients treated for classical Hirschsprung's disease between 1957 and 1990 at the Red Cross Children's Hospital, Cape Town, and review the current literature. The clinical and pathological findings of the cases have been studied to explore possible aetiological mechanisms. Our cases, like most of those previously reported, developed obstructive symptoms and acquired aganglionosis in pulled-through bowel which had been previously confirmed as ganglionated. Two patients had histological evidence of hyaline fibrosis of blood vessels in the segment of bowel with acquired aganglionosis. Such fibrosis and other features attributable to regional hypoxia were not found in the other three cases. It is suggested that ischaemia with fibrosis may have a pathogenetic role in some, but not all, cases of acquired Hirschsprung's disease. A plea is made for patients developing recurrent symptoms of Hirschsprung's disease, after adequate surgical correction, to be fully studied with repeated sequential biopsies in order to gain a better understanding of the entity.